Circuit breaker



July 28, 1953 H. A. HUMPAGE 2,647,191

CIRCUIT BREAKER Original Filed May 24, 1945 2 Sheets-Sheet 1 -36 Hman ALanr HUM pnae -L-va BY H. A. HUMPAGE CIRCUIT BREAKER July 28, 195`3 2 Sheets-Sheet 2 A Original Filed May 24, 1945 44 (Y INVENToR. 1' 70 'neozp/haznf/umpnas BY 5@ @niv Arronnzy.

Patented July 28, 195.3

signor, by mesne assignments, to Federal Electric Products Company, Newark, N. J., a corporation Original application May V24, v1945, Serial No.

595,556, now Patent No. 2,459,427, dated January 18, 1949. Divided and this application July 31, 1948, Serial No. 41,837

16 Claims. (Cl. 5200-168) This invention relates to automatic circuit breakers, and more particularly to circuit breakers of the type which are used for house lighting and other low amperage circuits.

The primary object of the invention is to provide a circuit breaker mechanism constituting a unit and comprising a housing in which said unit is mounted, the mechanism unit and the housing being so constructed and related that the mechanism unit can be calibrated and tested before being placed in the housing and so that the assembly of the mechanism unit in the housingis facilitated.

Another object of this invention is the provision of a multi-pole circuit breaker comprising a housing in which a plurality of circuit breaker mechanism units, one for each pole, are disposed for independent operation, the construction and arrangement of the housing and mechanism units being such that they can be interchangeably positioned within the housing.V

A further object of the invention is the provision of a circuit breaker comprising a housing for the circuit breaker mechanism having means formed in the housing as an integral part thereof for guiding the movable contact member.

A yet further object of the invention is generally to provide an improved small and inexpensive circuit breaker which is well adapted to be used, with reliability of operation, for vhouse lighting and other low amperage circuits in lieu of a switch and fuse combination.

The above and other objects, features and advantages of the present invention will befully understood from the following description considered in connection with the accompanying illustrative drawings:

In the drawings:

Fig. 1 is a front View of a circuit breaker embodying the present invention; Y

Fig. 2 is a side view thereof;

Fig. 3 is a rear view thereof; n y

Figs. 4 and 5 are end views as seen from lines 4-4 and 5 5 respectively of Fig. 2;

Fig. 6 is a side view of the circuit breaker, one part of the housing being removed, the movable contact members of the circuit breaker mechanisms being in their open positions; n E

Fig. 7 is a view of the left hand part of the housing, as illustrated in Fig. 6, and of the circuit breaker mechanism, showing the movable contact member in its closed position;

Fig. 8 is a sectional View on the line-Bof Fig. '7;

Fig. 9 is a sectional View on the liner, 9--9 of f Fig. 7;

Fig. 10 is a sectional View on line III-IIJ of Fig. 7;

Fig. 11 is a perspective view of av magnetic member forming a part of a circuit breaker mechanism; f

Fig. 12 is an end View of a combined terminal and stationary contact member of one type;

Fig. 13 is a bottom view of a combined terminal and stationary contact member of another type. Referring noW to the drawings in detail,- the circuit breaker of the present invention comprises a two part insulation casing or housing I0 formed of two identical or symmetrical parts I2, eachof said parts being formed of insulation material preferably by a molding operation. Each casing part I2 forms one-half of the housing, the two casing parts being secured in housing defining relation in any suitable Way, for example by bolts I4, the front and rear facing edges Ivand I8, the end facing edges 20 and the intermediate facing edge 22 of the two casing -parts I2 being in abutting surface to surface relation. Said facing edges are formed on the thickened edge portions at the inner orrconfronting sides of the opposed side walls of the housing, said thickened edge portions of Vsaid side walls extending peripherally of the housing. Thus, each casing part is formed with two recesses 24 which dene two chambers for two circuit breaker mechanisms. It Will be understood, however, that the 'housing can be provided for a single pole breaker in which case it can have a single chambenin lieu of the tWo chambers for the multi-pole circuit breaker illustrated herein. Each casing part I2 is provided at its opposite ends with open recessed portions 26 which form arcing chambers and in which terminal members and the stationary contacts Yof the two circuit breaker units are positioned respectively. The arcing chambers formed by the recesses 26 provided in the companion casing parts I2 are indicated at -28 in Figs. 4 and 5. The front of each casing part is provided with recessed portions which ydefine openings 30 through which, the handles 32 pro- .ject for manual operation of the circuit breaker mechanisms. Each of said handles is fixed kk,to pivot pin 34, the opposite ends of which are received in bearing recesses 36 (Fig. 8) formed in etact -member Y38.

metal of suitable thickness, is mounted in the chamber for pivotal movement by pivot pin 40, the opposite ends of .which are received in aligned bearing recesses 4l )in the .companion casing parts l2. Said movable contact member 38 is provided at one end thereof with a contact 42 which is engageable with and disengageable from a companion stationary contact 44 carried Joy a terminal member 4B or by a .terminal member 48 both of which will hereinafter be more particularly described. The casing 'l0 -is provided with means for guiding movable contact member 38, for which purpose the thickened or inwardly projecting end portions--43-of-the companion casing parts I2 are vprovided -with Jrecessed portions 45 whichdene a'guide slot 4l (Figs. 9 and 10) through which an end portion 48 projects with slight clearance. Thus,.it'fwill be noted that the means for guiding the mov- .-able. contact :member T38 of -each ,circuit breaker mechanism is formed in the casing as integral -A thermal-current responsive thermostatic bi-metallic flexible strip, is lwelded or otherwise secured atone end thereof toa side edgefof movable vcontact.member 38. .The free -endof v`lfiiemetallic stripll isarranged to releas- .ably .engage the end of vone arm of a lever `52 ,-,pivotally mounted on the endof movable con- ..tact-member.38 .opposite .to the end which carfendv of said-.handle ,Asclearly shown .in the drawings, .each =movable `rcontact .member 38 is .provided fwith .ya laterally-.offset portion .58 so .that 4`.each -circuit .breaker ,mechanism can com- .prise a'movable .contact member of the same .construction as well as A other `parts of ,the same rconstructionand' bemounted interchangeablyY in -either .of themechanism chambers of thercas- ...ing .,Awcoilspringf is operatively -interposed ibetween the=movable contact member .38 and the .companion handle 32 for biasing the movable fcontact .member to its Open position. One end .ofsaid-spring engages ya .lug .62 iixed .to .handle .-32 ,and the :other .end vof said spring Vengages a .lug6.4.integral with the companion movablecon- The `mechanism 4constituted .byfhandle 32 movable vcontactmember 3 B'therma'l vstrip-lllever-SZ and link-54 issimilar to .and op- .erates substantially in vthe same .Way -as .correesponding 1mechanism.in.the .circuit breaker fdis- Lclosed-insaid .Christensen .Patent No. 2,209,319. Also .aslhere shown themovable contact member 338;-isprovidedwitha slot.64 and a tapered screw .66 for calibrating ,the=cir.cuit.breaker as Yshown -and-.described infsaid Christensenpatent. It will lbeunderstoodthat member operates ftolatch the `manually .operable actuating mechanism to .the.movable contactfmemberand to unlatch the actuating mechanismirom the movable contact member, Ythe .unlatching taking kplace by deec- .tion of .member .50 vfrom engagement .with lever ..52 .upon vtheoccurrence of anoverload or under other. abnormal .predetermined current .conditions in .the .circuit controlled `by the circuit breaker. VWhen member'isdeected vfrom en- .;.gagement with ',the companion lever"52,spring '60 is effective to move contact member `38 to its open position, i. e., from the position illustrated in Fig. 7 to the position illustrated in Fig. 6. It Wll .be. noted ,that the inner end 47A of the guide slot 41 constitutes a stopfor member 38 to limit the opening movement of the latter. The intermediate thickened wall portion 49 of each casing part l2 terminates short of the rear Wall of .thecasing to provide a recess into Which levers 52 are movable, as shown in Fig. 6, and to provide shouldersf which serve as stops for said levers, respectively.

The thermal element 50 is connected in series with movable contact member 38 and the circuit which is to becontrolled by the circuit breaker. Forfthispurpose'a flexible metallic conductor or :connector'l is --connected to said thermal element, preferably adjacent to free end thereof, .and-.toacompanion terminal member '10. There are two terminal members 10, one for each of v-thegtwo thermal members A.50 of the two `circuit breaker mechanisms. These .two terminalmembers 'l0 .are positionedin the'recess below intermediate casing portions 49,. and aremechaniaclly and electrically ,connectedpreferably removably, toa-:common vlead orbus bar 'l2 in any suitable Way ,as ,by a screw 14 which passes rthrough .alignedaperturesin said thermal member-1,0 and is threaded into atappedhole in bus bar 12. Y.An .opening .16 Vis provided in the backofcasing l0 Afor access .to screw v'HL The lead or bus bar l2 enters .the casing throughafslot 18 in theside thereof. Said slot is provided in each 4of ,the companion casing parts`|2. Thus,the terminal -lead or busbar 'l2 can vbe long-enough topro ject vinto .a pluralitypfcasings .l0 Which-.may be disposed .with rtheir -respective'side Walls in adjacent-or abutting vside byside relation. The ,outer portionbf ybus .bar 12 lis provided with-a vterminal member Y8|). It .--Will `:be noted vthat 'the provision of the separate individual terminals 1,0 forthe two .circuit breaker mechanisms provides for independent calibration and testing :of the different Ycircuit breaker vmechanisms and also provides for different current 1carrying ...capacities of the two circuit vbreaker 'mechanisme respectively. Thus, `whilezthetwo circuit; breaker :mechanisms .are mounted :in a common housing, they :can be v,of :different fcurrent -carryingfca- Afpacities .orfratings although, of course, vthey .can

:have the samecurrentacarrying capacities orfratings. As here shownpthecircuit breakerv mecha- Anisms are illustrated "for different -current car- .ryingcapacities-.as=indicated by the differentrter- `minal members 1146 aand 548 for the two =inde .pendcntly operable circuit breaker mechanisms, respectively. More particularly? the circuit breaker mechanism at the right of the casing, as i1- `rlustrated'in Fig. '6 is designedfor a higher current carrying capacity Ythan the other -circuit breaker mechanism and'for thatV purpose the terminal member 46 for said first mentioned cir- -cuit vbreakermechanism has a higher current carrying capacity than the terminal member '4B -for Ythe vother circuit breaker mechanism. ,Also lit will be noteduthat the terminal members 10 when Vsecured Vtothe bus bar 'T2 `internally .o'f the housing hold the ylatter fin .stationary vposition, since said vterminal members are Ypositioned '1n the space between confronting wall portions of the housing with the edges o'f .said terminal members abutting 'or closely adjacent .to the.. inner surfaces lof said adjacent portions, respectively, of the housing.

The casing -Iiris con-structed'to hold the'terminal members 46 and 48 in such manner as to. obvate theneed for screws or other fastening means. For this purpose the casing I8 is provided with aligned recesses 82 formed in the companion casing parts I2 to receive either the projections 83 of the terminal member 46 or the projections 84 of the terminal member 48. In addition to the recesses 82, casing l is provided at each end thereof with aligned recess 86 formed in the two casing'parts i2 to receive an end portion 88 of the member 48. It will be noted therefore, that the casing is constructed land arranged so that either terminals such as 46 or terminals such as 48 can be mounted and secured at both ends of the casing or, as here shown, a terminal such as 46 can be mounted and secured at one end of the casing and a terminal such as 48 can be mounted and secured at the opposite end of the casing. It will be understood that when the terminals are positioned with their projecting portions 83 or 84, as the case may be, in the companion recesses 82 and the two casing parts are fastened together by the bolts .|4, or in any other suitable manner, with their inner faces in abutting relation, the terminal members are securely yheld or fastened to the casing, in position between the opposite side walls thereof, thus eliminating the use of extraneous fastening devices. It will be noted that, as here shown, members 46 and 48 carry the stationary contacts 44, which are preferably welded thereto, and thus constitute combined terminal and stationary contact members, and that when said combined members are mounted on the oasing said stationary contacts are disposed in the respective arcing chambers in position to be releasably engaged by the contacts 42 of the companion movable contact members 38, respectively.

The thermal current responsive member 58 is operable not only in response to the heating effect of the current passing therethrough, but is also operable under the control of electromagnetic means for eiiecting disengagement of the companion relatively movable contacts 42 and 44, and the arrangement is preferably such that as here shown the electromagnetic means is energized by the current which passes through the thermal current responsive member 58. For this purpose an electromagnetic member 98 is mounted on member 58 near the free end thereof and a companion rigid armature 92 is disposed in spaced confronting relation to electromagnetic member 98. As clearly illustrated in the drawings, the inner end 94 of armature 92 is fixed, preferably by welding, to the fixed end of thermal member 58. The electromagnetic member 98 is secured to the thermal member 58 by lateral projections 98 which are integral with thermal member 58 and which project through openings 98 in the companion electromagnetic member 98. Preferably, openings 98 are somewhat larger than the companion provisions 96 to allow relative movement between thermal member 58 and electromagnetic member 98 so as to maintain the parallel relation between the confronting portions of kmember 98 and the companion armature 92 without impairment by the deflection or flexing of thermal member 58. As shown in the drawings, magnetic member 98 straddles the member 58 by which it is carried. Said member 98 is formed in one piece of soft sheet steel or other suitable sheet `metal and is provided with an end wally opposed side walls inwhich the openings 98 are provided, and with out-turned end portions 99 Fig, ll) which are arranged in surface-confronting relation to the adjacent surface of armature 92. Openings 98 are positioned so that said end wall of member 98 is spaced from member 58, and there is a slight clearance between the edges of member 58 and the inner surfaces of the side walls of member 98 so that the latter has a free relative movement on member 58. It will be understood that upon the occurrence of an overload in excess of that for which the circuit breaker is designed to open under the control of the thermal member 58 by fiexing of the latter in response to the heating thereof, the electromagnetic device is operable instantaneously to effect, disengagement of the companion contact members. It'will be understood that upon the occurrence of such excess overload the magnetic attraction between members 98 and 92 results in the deflection of thermal strip 58 for disengaging the latter from the companion arm of the lever 52, and in this connection it will be understood that since member 92 is rigid and thermal member 58 which carried member 98 is flexibleI member 98 is movable by magnetic attraction toward member 92, thus deflecting or unlatching thermal member :58 from the companion lever 52.

The housing I8 is provided with means to en-f able it to be secured to a supporting plate, panel, or other support. For this purpose the casing parts I2 are provided with recesses |88 in which nuts |82 fit and are held against rotation by the side walls of the recesses. Holes |84 are provided at the back of the housing for screws (not shown). which engage nuts |82.

This is a division of my application which originally issued as Patent No. 2,459,427, dated January 18, 1949, and which was reissued on January l0, 1950, as Re. 23,188.

Certain features shown but not claimed herein or in my Reissue Patent No. 23,188 are claimed in my divisional application Serial No. 351,267, filed April 27, 1953. f

While I have shown and -described the preferred embodiment of my invention, it will be under-v stood that the latter may be embodied otherwise than as herein speciiically illustrated or described and that in the illustrated embodiment certain changes in the details of construction and in the arrangement of parts may be made without de parting from the underlying idea or principles of the invention within the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is 1. In an automatic circuit breaker comprising an insulation housing and a circuit breaker mechanism disposed therein, said mechanism including a movable Contact member provided with a contact, and said housing comprising opposed side walls between which said movable contact is mounted for movement, a combined terminal and stationary contact member positioned externally of said housing and disposed between said side walls and provided with a contact positioned for releasable engagement by said movable contact. portions of said opposed walls on the outer side of the housing having aligned recesses .therein and said combined member having oppositely extending substantially similarly dimensioned portions engaging said opposite side walls in said recesses, respectively, and thereby securing said combined member to said housing.

2. In an automatic circuit breaker, a housing consisting essentially of two symmetrical parts formed of insulation material, each of said parts having an outer side wall and having thickened` edglportionsprojecting from the inner` side. of the sideAv wall andextending peripherally thereof andlalbuttingthe similar thickenededge portions 'ofL-theptherside wa-ll thereby forming ar chamber internally of the housing, the thickened portions ofthe two casing parts having opposed recesses thereindening a guide slot, a circuit breaker mechanism mounted in said chamber and includingfa-movable contact member movable in said slotland-guidedthereby said-side walls having in'- tegral portionsprojecting` outwardly beyond said guideslotandlvdening an external open recess atoneend of the housing, and a stationary contact membermounted in said external recess and h'eldinL-positicn by complemental substantially similarly dimensioned' formations on said projecting portionslof said side walls,- said stationary and movable Contact members having companion oontactswhich engage and Vdisengage eachother inl-said' recess in the operation of the circuit f breaker.

3;Inan .automatic circuit-breaker, a housing consisting essentially of two symmetrical parts orinedofin'sulation material, each of said'parts having an outer side wall and having thickened edgeporltion's projecting from the inner side of the' fside wall and extending peripherally thereof andfalbuttingthe similar thickened'edge portions offithe otherside wall thereby forming a chamber internaliyofthe housing, the thickened portions of the two'casing parts having opposed recesses therein 4deiining aY guide slot, a circuit breaker mechanism mounted in said-chamber and 'includingo-movable contact member movable in said slotl Sandi .guided thereby, said side walls having :i

integral portions` projecting outwardly beyond said guide slot and delining an external open reaesszat one' end of the housing, anda stationary Contact member mounted! in said external recess andv disposed entirely' externalllyvofl said chamber beyond said guide slot, said stationary contact rmen'iber`A partitioning said? recess to provide an arcin'g: chamber therein, .anda terminal connector member; positioned in said recess and secured directly to :said stationary. contact member in said external' Yarcing chamber, said .stationary and movablecontact members having companion contactsiwhich' engage and disengage each other in 'said'zrecess inthe operation of 'the circuit breaker.

4 Iman automatic circuit breaker, a housing consisting essentially of two symmetrical parts formed oft insulation material, each of said parts having an outer side wall vand having thickened edgeiportions 'projecting' from the inner side of thefsidecwall and extending peripherally thereof and'abuttingthe.similar thickened edge portions of .the 'otherside wall thereby formingv a chamber internally of thehousing, the thickenedv portions of the-"two casi-ng' parts having opposed recesses therein-,deijning a guide slot a circuit breaker mechanismmounted linsaid chamber and includinga: movable contact member movable in said slot :and guided' thereby, said side walls having integral: Iportions projecting' outwardly beyond said guide slot and deiining an-external open recessizat. one'fendlof the ,housing7 and a stationary contact member mounted in said external recess and disposed :entirely externally of said chamber beyondisaidiguide slot, and a terminal connector member. positioned in-saidrecess and secured directly to said stationary contactmember in said external recess,- said stationary and movable contact .membersLhaVing companion contacts which engageland .disengage each other in said vrecess inathe Aoperation of thecircuitJbreaker, and co 8 operatingrcrmationslon said? projecting portions of saidside walls disposed below saidstationary contact member in--sa'id-external recess and posi'- ti-oned laterally of and adjacent to said cemp'anion contacts andi forming an arc chuteopen t'o'thevsp'ace between said contacts in the ldisengaged condition of thelatter.

f5` In: 'an-automatic circuit breaker, a housing consisting essentially ofy two' symmetrical parts formed of insulation'material, veach of said-parts having an' outer' sidewall andi having thickened edge portions-i projecting from Athe inner slde'oi' tlie side waflland Aextending per-ipherallythereof and abutting the similar thickenededge portions of the other side wall-thereby forming a chamber internally of the housing, the thickened portions ofthe two4 cas-ing parts having opposed recesses therein de'ning arguide slot, aA circuitl breaker mechanism mounted in said chamber and includ'- inga movable contact member movable-in said slot and-guided thereby, said side-'walls 'having integral poitionsprojecting outwardly beyond sai-dguide slot? and' dening an external open rece'ssat oneendof` the housing, `and a stationary contact member mounted inV saidA externalrecess and held iii-position by complemental formations on'sa-id project-ing portions of Vsaid side walls, said stationary and movablecontact Vmembers having companion-contacts which engage andl disengage each other in said -recessin the operaticnof the circuitl breaker, andAA cooperating formaticns'on said-projecting portions of said' sidewalls underlying saiid stationary contact `memberin said external recess -and'positioned laterally of and-adjacent 15o-saidcompanion-'contacts and forming an arc chute open tothespace'between said contacts in the Ydisengaged condition ofthe-latter.

6. In an automatic circuit breaker, a housing consisting essentially of two symmetrical parts formed of insulation material, each of said Darts having an outerside wall and having thickened edgeV portions projecting from the inner side o'f the side-wall and extending peripherally thereof and abutting `thesimilar thickened edge portions of the other side wall thereby forming a chamber internally of the housing, the thickened portions of the two casing parts having opposed recesses therein deiining a guide'slot, a circuit breaker mechanism mountedi-n said chamber andinc'luding' a movable contact member movable in sa'id slot andv guided thereby; said side Walls having integral `portions projecting outwardly beyond said guide slot and deningan external open re'- cess atene-end of the housing, and a stationary contactmembermounted in said external recess andheld '-inpositionby complemental formations onsaid projecting portions of said side walls, said stationary andVV movable contact members having companion contacts which engage and disengage eachother in -safid recess in the operation of the circuitbreaker, anda terminalconnector member positioned in said recess and secured directly to said stationary contact member in said external recess and` cooperating formationsv on said projecting portions of said side Walls underlying said terminaloonnector member and said stationary contactmember in saidexternal recess and positioned laterallyy of and adjacent to said companion contacts and forming an arc chute open toA thespace betweensa'id contactsl in thev disengaged-'fconditionof thelaitter.

"7l In an automatic circuit breaker, a housing formed of? insulation material and comprising means including opposed side walls forming al chamber; v a circuit breaker mechanisml mounted 9 in said chamber between said side walls and including a movable contact member mounted within the chamber for movement between and parallel to said side walls, said housing having a chamber defining wall extending transversely of said side walls therebetween and provided with a slot through which said movable contact member projects from the interior to the exterior of the chamber and which constitutes a guide for said member, a contact carried by said movable contact member exteriorly of the chamber, a terminal connector disposed at the outer side of said transversely extending wall in position between said side walls, a stationary contact member fixed directly to said terminal connector and disposed between said side walls at said outer side of said transversely extending wall and provided with a contact positioned exteriorly of said chamber between said side walls in position for releasable engagement by said movable contact, and integral formations on said side walls, respectively, in the space therebetween and disposed below said stationary contact member and externally of said transversely extending wall forming an arc chute having its inner end adjacent said contacts and its outer end adjacent the outer ends of said side walls.

8. In an automatic circuit breaker, a housing formed of insulation material and comprising means including opposed side walls forming a chamber, a circuit breaker mechanism mounted in said chamber between said side walls and including a movable contact member mounted within the chamber for movement between and parallel to said side walls, lsaid housing having a chamber defining wall extending transversely of said side walls therebetween, said side walls having portions projecting outwardly beyond said transverse wall and defining an external open recess at one end of the housing, a stationary contact member mounted in a portion of said external recess and dening a boundary for the remaining portion of said recess, said remaining recess portion constituting an arcing chamber, va slot defined in said transverse wall through which said movable contact member projects into said arcing chamber, a contact carried by said movable Contact member for movement in said arcing chamber, and a contact carried by said stationary contact member and disposed in said arcing chamber for releasable engagement by said mov-V able contact.

9. In an automatic circuit breaker, a housin formed of insulation material and consisting essentially of two symmetrical parts disposed in abutting side by side relation and each having a recess at its inner side forming a chamber with the recess of the other part, a circuit breaker mechanism including a pivotally movable contact member mounted in said chamber, said two casing parts having abutting portions forming a transverse outer end wall of said chamber, each of said abutting portions having a recess which confronts the recess of the other abutting portion forming a slot open at both ends thereof, said two casing parts having portions projecting outward# ly beyond said transverse wall and dening an external open recess laterally of said chamber, a stationary contact member mounted in said external recess and dividing the latter to form an arcing chamber, said movable contact member projecting through said slot from the interior of said nrst mentioned chamber into said arcing chamber, a contact carried by said movable contact member at the part thereof which is disposed in said arcing chamber, and a contact carried by said stationary contact member and disposed in said arcing chamber for releasable engagement said movable contact.

10. In an automatic circuit breaker, a housing formed of insulation material and consisting essentiallyvof two symmetrical parts disposed in abutting side by side relation and each having a recess at its inner side forming a chamber with the recess of the other part, a circuit breaker mechanism including a pivotally movable contact member mounted in said chamber, said two casing parts having abutting portions forming a transverse outer end wail of said chamber, each of said abutting portions having a recess which confronts the recess of the other abutting portion forming a slot open at both ends thereof, said two casing parts having portions projecting outwardly beyond said transverse wall and defining an external open recess iaterally of said chamber, a combined terminal and stationary contact member mounted in said external recess and dividing the latter to form an arcing chamber, said movable contact member projecting through said slot from the interior of said first mentioned chamber into said arcing chamber, a contact carried by said movable contact member at the part thereof which is disposed in said arcing chamber, and a contact carried by said stationary contact member and disposed in said arcing chamber for releasable engagement by said movable contact, said projecting wall portions having aligned recesses therein and said combined member having oppositely extending portions engaging said projecting wall portions in said recesses respectively, and thereby securing said combined members in said housing.

ll. In an automatic circuit breaker, a housing formed of insulation material and comprising means including opposed side walls forming a chamber, a circuit breaker mechanism mounted in said chamber between said side walls and in-v cluding a movable contact member mounted within the chamber for movement between and parallel to said side walls, said housing having a chamber dening wall extending transversely of said side walls therebetween and provided with a slot through which said movable contact member projects from the interior to the exterior of the chamber and which constitutes a guide for said member, said side walls having portions projecting outwardly beyond said transversely extending wall and defining therewith an external recessopen at one end of the housing, a stationary contact member mounted in said external recess and disposed entirely externally of said chamber beyond said transverse wall, and a terminal connector member positioned in said recess and secured directly to said stationary contact member in said external recess, said stationary and movable contact members having companion contacts which engage and disengage each other in said recess in the operation of the circuit breaker.

12. In an automatic circuit breaker, a housing formed or insulation material and comprising means including opposed side walls forming a chamber, a circuit breaker mechanism mounted in said chamber between said side walls and including a movable Contact member mounted Within the chamber for movement between and parallel to said side walls, said housing having a chamber defining wall extending transversely of said side walls therebetween and provided with a slot through which said movable contact member projects from the interior to the exterior of the chamber :and ywhich constitutes .a guideiforssaid membeL-saidfside :walls having portions projecting outwardly beyond; said transversely extending wall and defining therewithfan-external recess openfat one end-oi the housing-a stationary contact-,member :mounted insaid external recesszand disposed entirely externallyzof said v` cliamber'beyoud-said transversewall, and a terminal 'connector fmemberpositioneddn; said recess .and-securedadirectly to vsaid stationary contactmember in said externalv recess, said stationary and movable .contact members' having companion Vcontacts which engage and disengage each other'infsaid recessin ythe operation of the circuitlbreaker, and cooperating .formations ...on f said i projecting portions-of said sidewalls, said formations beingfdisposed in -saidvexternal recess relativeto both said :stationary 'contact .member A. and `said terminal connector member, said formations being positioned laterally of -and .adjacent-to said companion contacts land forming .an are chute open .to the spacevbetweensaidcontacts in `the disengagedcondition of the latter.

13. Inan automatic circuitbreaker, Aa housing consisting essentially of two symmetrical parts formed of insulation material, each ,ofsaid-parts having any outer side vr'wall-and .having thickened edgeportions projecting fromthe inner sideof the side -wall fand; extendingy peripherallythereof and abutting the similar thickened edge portions ofthe vother side wall therebyformingI a chamber internally.` ofthe housing, the l.thickened portions ofthe two casingipartshaving opposed -recesses therein .fdeiining -a guide slot, a circuit'breaker mechanism lmounted in -said chamber andincluding -a movable contact member -movable .in said slot and guided thereby, said side-Wallsfhaving nintegral portions projecting outwardly ibeyond 'saidsguider slot and fdenning Ywith said guide slot; deiining portions anf,externalfopenrecess; at one Tend of .the rhousing, fa stationary lContact member mounted in .said -extern-al Arecess 4and disposed .entirely externally rof -said chamber'zbeyond said guideslot, and ater-minal connector member positioned in said recess and secured directly A.to #said stationary :contact 'member :in saidr external recess, said 'stationary .and movable Contact members shaving Vcompanion .contacts which-engage and disengagegeach other vinsaid recessin the'operation of the .circuit breaker.

14. .In anfautomatic circuit breaker, `a housing formed Aof insulation material and consisting essentially of two symmetrical parts Adisposed abutting side by side .relation andeach having azrecess-atv itsi inner side; formingfa Achamber with the recess of the other 'partfa Ycircuit breaker mechanism including a pivotallycmovable contact member v*mounted insaid chamber, saidtwo casing parts having abutting portionsformingsa transverse outer end wall of said chamber, each of :saidabutting portions having `a recess which confrontsthe recessof/the other abuttingportion .forming a slot open at both ends thereof, said parts having portions'projecting outwardly beyond -said transverse rwall and dening therewith an external recess open at one :end ofthe housing-said :movable contact member .projecting through :said slot from 'the interior of said chamber finto said external recess, a ,contact carriedbyfsaidzmovable contact member atthe part :thereof rwhich isdisposed in said external recessxaistationaryfcontact member mounted in said `:external recess'for releasable engagementby saidscontact of-y thel movablecontact member, and afterminaluconnector member positioned ingisaid recess .fand .secured directly .to said stationary contactfmember.

.15. .In an automatic circuit breaker;v a housing formed ofrinsulationmaterial.and consisting essentially .of two symmetricalparts disposedin abutting .iside 'by'side relation and each having awr-ecess-atits inner side forming a chamberfwith theirecess-.of the other part, a circuit breaker mechanism including aa pivotally movable contactmember mounted in'said-chamben'said two casing fpartsihaving abutting portions forming aftransverse Aouter end wall of said chamber, Aeach of. said abuttingfportions having a recess which confronts ithe :recessof thefother abutting portion formingaslot-.openeat both ends thereof, said Lparts having portions projecting outwardly beyond.-saidtransverse wall and defining therewith `.anfvexternal-recess open at one end of the housing, said movable contact member projecting through rsaidslotfrom the interior of said chamber .into .said external recess, a contact carried .bysaid movable-contactmember at the part :thereof which is'disposed in said external recess; and a stationary contact member mounted in said-.external recess 'for releasable engagement byssaidcontact Aof the movable contact member.

L6.ln zin-'automatic -circuit breaker comprising an insulation housing and Va circuit breaker mechanism :disposed therein,said mechanism including a movable contactV member provided with afcontact,':and saidhousing comprising opposed side walls-between which said movable contact is mountedffor movement, a-combined terminal and 'stationary-contact member positioned externallyrof :said "housing and disposed between saidside'walls-and provided with a contact positione'd for releasable'engagement by said movable c0ntact,:portionsof said-opposed walls on the outer side of the housing having aligned similarly dimensioned recesses therein and said combined member having oppositely extending portions each substantially similarly dimensioned, lsaid portionsaengaging said opposite side walls in said recesses, respectively, and thereby securing said combined-.member to said housing.

EHAROLD ALBERT HUMPAGE.

-References Cited 4inthe le of this patent YUNITED STATESPATENTS Number Name Date Y2,130,369 Christensen Sept. 20, 1938 2,132,629 .Jackson Oct. 1l, 1938 2,150,013 VonHoorn Mar. 7, 1939 2,269,171 Benander Jan. 6, 1942 2,335,007 Hutt Nov. 9, 1943 21,367.3.82 Taylor Jan. 16, 1945 237.0.,206 .Taylor Feb. 27, 1945 2.416.266 rLandmeicr Feb. 18, 1947 

